Human body communication is a technology for performing data communication using a human body. In other words, the human body communication does not use wired or wireless communication, but uses the human body as a transfer medium of an electrical signal. There are many ways in human body communication. As an example, human communication may use a change in current flowing in a human body. In other words, the human body communication may be performed by contacting an electrode of a transmitter and a receiver with the human body and changing a fine current. As another embodiment, human communication may use a change in surface electric field of the human body. In this way, the human body communication may transmit various data by taking the human body as a medium.
When human body communication using a human body as a transmission medium is used, communication between mobile devices or communication between a fixed device and a user may be performed through a contact of the user. For example, communications between mobile devices such as a digital camera and a smartphone and peripheral electronic devices may be performed through a contact of a user. Printing, credit card payment, TV reception, entrance control system, or transportation fee payment at the time of riding, etc., may be performed through a contact of a user. In addition, communication with electronic devices attached to the human skin or inserted into a human body may be performed by adopting the human body as a medium. Human body communication using capacitive coupling is standardized as wireless body area network (WBAN)-related international standard IEEE 802.15.6 WBAN. Such human body communication using capacitive coupling may be usable as a communication method of a wearable device.